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Density currents from the Colorado River inflow extend many kilo- ers into the reservoir during periods of high spring flow (Johnson and ritt, 1979). The inflowing water may have stimulated squawfish to e upstream into the mixing zone. Low flows during 1981 might not have vided the necessary stimulus for upstream movement (Figure 3). During the 1980 season, (April 26 - June 18), discharge ranged from m3/sec (24,060 cfs) to 1,806 m3/sec (63,790 cfs) and averaged 80 m3/sec (45,203 cfs). Discharge during the same period in 1981 ged from 198 m3/sec (7,000 cfs) to 655 m3/sec (23,120 cfs) and raged 378 m3/sec, (13,352 cfs). Seasonal and temperature differ- es may also have had an effect on capture of squawfish in the mixing e during 1980 and 1981. Peak catches during 1980 were in late April early May (Figure 4) when water temperature ranged from 12-16° C -60° F). During 1981, however, sampling was initiated until late May n water temperatures already exceeded 16° C (60° F) (Figure 3). Another possibility is that squawfish captured during 1980 were idents of the mixing zone which resembled a large, slow moving er. During 1981, habitat conditions (depth and flow) were radically nged from those present in 1980. Mud and silt bars formed during 1980 e exposed in 1981, the channel was narrower and shallower (3-5 meters 9-11 meters), current velocity was greatly reduced, and there were er and smaller side eddies during 1981 than 1980 (Figure 5). These .nges in the physical habitat may have made the mixing zone less table for adultsize squawfish, hence fewer were collected. It is difficult, if not impossible, to draw conclusions concerning awfish movement based on tracking a single fish. The tagged fish, a ge 4,082-gram adult, evidently moved from the mixing zone over 37 km miles) toward the main body of the reservoir in less than 3 days. project needs to be repeated in years of normal river flows to ermine source of the squawfish and reason for their concentration in Colorado River inlet area. REFERENCES CITED nson, N. M., and D. H. Merritt. 1979. Convective and advective circulation of Lake Powell, Utah-Arizona, during 1972-1975. Water Resources Research 15(4):873-884. sons, W. R., and R. V. Bulkley. 1980. Adult striped and feeding, Colorado River Inlet, Lake Powell, Progress Report. U.S. Fish and Wildlife Service 0008-1061. Utah Cooperative Fishery Research Unit, bass movements 1980. Annual Contract 14-16- Logan. 21 pp. 279